The availability of exact navigation means like, e.g., GPS, to common transport vehicles, for example cars, has greatly facilitated route navigation (GPS=Global Positioning System). The driver of a vehicle no longer has to look for his way in paper road maps. Instead he is conveniently guided by visual and/or accoustic path information offered via an electronic navigation system.
Basically, navigation systems can be distinguished between on-board and off-board systems. On-board navigation devices are stand-alone devices which hold a road map database of a preferred travel area (usually stored on an exchangeable data carrier like,. e.g., CD-ROM, DVD) and calculate a route by means of an on-board processor. To adapt to changes of the road network, the road map database stored in the navigation device must be updated once in a while.
With the increasing capabilities of wireless communication networks like, e.g., GSM or UMTS, the off-board solution becomes increasingly important (GSM=Global System for Mobile Communication, UMTS=Universal Mobile Telecommunications System).
For example, EP 1 274 058 B1 describes that a request for route information is communicated via a wireless communication network from a driver's communication terminal to a remote central server continuously provided with updated road map databases and current traffic conditions. The central server calculates the route and transmits the corresponding route information back to the driver. Thus the need for complex navigation devices in the vehicle is avoided, the driver can navigate by means of a simple and inexpensive communication means, like a mobile phone, and the calculated route information includes the latest changes in road network and traffic condition.
It is the object of the present invention to provide an improved navigation service.
The object of the present invention is achieved by a method for providing vehicles with a navigation service, wherein the method comprises the steps of building a group of two or more vehicles, each vehicle comprising a communication unit coupled with a navigation unit, wherein one vehicle of the group is classified as master vehicle leading the group and the remaining vehicles of the group are classified as slave vehicles following the master vehicle; determining geographical position data of the master vehicle and the slave vehicles; communicating geographical position data of the master vehicle and the slave vehicles to one or more data processing units; calculating by the one or more data processing units for each of the slave vehicles route instructions in accordance with the route traveled by the master vehicle based on the received geographical position data of the master vehicle and the respective slave vehicle; and communicating the respective route instructions to a driver of the respective slave vehicle.
The object of the present invention is further achieved by a navigation server for providing vehicles with a navigation service, the navigation server comprising a data base for storing communication addresses assigned to two or more vehicles, each vehicle comprising a communication unit coupled to a navigation unit, a group building unit for building a group of the two or more vehicles, wherein one vehicle of the group is classified within the data base as master vehicle leading the group and the remaining vehicles of the group are classified within the data base as slave vehicles following the master vehicle, an interface unit for receiving geographical position data of the master vehicle and the slave vehicles via a communication network, and a data processing unit arranged to calculate for each of the slave vehicles route instructions in accordance with the route traveled by the master vehicle based on the received geographical position data of the master vehicle and the respective slave vehicle and to transmit the route instructions to the communication units of the slave vehicles via the communication network based on the communication addresses stored in the data base.
The object of the present invention is further achieved by a navigation system for providing vehicles with a navigation service, the system comprising two or more navigation units having a data processing unit, each navigation unit assigned to a vehicle and coupleable with a respective communication unit for communicating via a communication network, and an output unit, wherein the navigation system comprises a mediation server arranged to build a group of two or more vehicles, wherein one vehicle of the group is classified as master vehicle leading the group and the remaining vehicles of the group are classified as slave vehicles following the master vehicle, to store communication addresses the communication units assigned to vehicles of the group, that each data processing unit assigned to the slave vehicles is arranged to calculate for the respective slave vehicle route instructions in accordance with the route traveled by the master vehicle based on received geographical position data of the master vehicle and the respective slave vehicle, and to transmit the route instructions to the output unit to be communicated to the driver of the respective slave vehicle.
The use of the invention offers an improved way of providing vehicles with a navigation service.
Travelling together in a group of two or more vehicles is a driving situation, e.g., wherein a driver familiar with a route in his vehicle leading the group and followed by the other vehicles of the group, or likewise, a couple of families each in their own vehicle travelling together to the same holiday destination.
Due to bad weather conditions, heavy traffic, unforeseen stops, or similar reasons, intervisibility among the travelling vehicles may be intermitted or even lost. Particularly, this poses a problem in densely populated areas with heavy traffic. The invention prevents the following vehicles of the group to deviate from the route traveled by the leading vehicle and to eventually lose their way. The accurate and reliable guidance of the vehicles of the group shortens the journey time because the chance of following vehicles getting lost is minimized. By use of the invention, the situation that lost drivers are forced to cumbersomely rejoin the group by waiting, searching, or by calling over mobile telephones is anticipated.
Conventionally travelling together in a group of two or more vehicles makes high demands to the drivers as they must pay attention both to the traffic and the leading and/or following vehicle. The invention facilitates relaxed driving conditions when travelling in a group of vehicles, both for the leading vehicle as well as for the following vehicles. It relieves the high burden of the drivers, the drivers do not become easily exhausted and are less likely to get involved in a traffic accident. Furthermore, the invention offers a convenient possibility to signalize a request for a stop from one of the rear vehicles to the vehicle leading the group.
Further advantages are achieved by the embodiments of the invention indicated by the dependent claims.
According to a preferred embodiment of the invention, the positions of the master vehicle and one or more slave vehicles are indicated to the driver, e.g., by blinking or colored dots, on a road map which is electronically displayed on a display. The display can be integrated within a communication unit or a navigation unit located in the vehicle. The electronic road map as well as the positions of the vehicles can also be displayed on a stand-alone display, which may be permanently integrated in the vehicle, e.g., within the dashboard. By indicating the current position of the master vehicle and one or more slave vehicles, the drivers are provided with a better orientation.
The method according to the invention can be implemented both as an off-board and as an on-board version. Besides, there is also a variety of hybrid solutions which contain elements of both the off-board and the on-board type. Basically, no separate route to the destination is calculated for the slave vehicles of the group, but the route instructions the slave vehicles are provided with are based on the route taken by the master vehicle. For example, route instructions are calculated based on the current position of the respective slave vehicle and a route destination represented by the current position of the master vehicle.
In a preferred embodiment of the off-board version, the vehicles transmit their current position at certain temporal intervals to the remote central server where the positional data are processed with regard to underlying road map data and traffic condition data. In a preferred embodiment of the on-board version, the master vehicle transmits its current position to all slave vehicles of the group so that every slave vehicle of the group is provided with the complete positional data of the master vehicle. The route instructions are not calculated centrally in a central server, but are generated locally in the navigation unit of each vehicle based on the received position data. Further, it is possible that all vehicles of a group transmit their current position data to all other vehicles of the group so that every vehicle of the group is provided with the complete position data of the group.
According to one embodiment of the invention, the driver of the master vehicle is instructed not to exceed a certain speed or even to stop if one of the following slave vehicles is not able to keep pace. It is possible that the driver of the master vehicle travels too fast because he is so familiar with the traveled road that he does not notice any more the difficulties it poses to the drivers of the slave vehicles. When the—temporal and/or spatial—distance between the master and one of the slave vehicles exceeds a predefined limit, the driver of the master vehicle receives corresponding instructions which allow the slave vehicles to catch up. These instructions can originate—in the off-board version—in the central navigation server or—in the on-board version—in the data processing units contained in navigation units of the vehicles and may be issued visually and/or acoustically to the driver.
It is possible that the drivers start on a long travel to a remote destination which is unknown to each of the drivers. Then, in order to equally distribute responsibility, the drivers of the vehicles may have arranged among them to cyclically take over the status of the leading master vehicle. When the central server, the mediation server or the data processing units of the vehicles, respectively, receive a request from a slave vehicle regarding the transfer of the master status from the current master vehicle to the slave vehicle, the classification of the vehicles of the group is revised, and the requesting slave vehicle is granted the master status while the up-to-then master vehicle becomes a slave vehicle. It is possible that the driver of the master vehicle or the drivers of all vehicles have to confirm such a request before the master status can be transferred to another vehicle.
Further, it is possible that an additional vehicle wishes to join the group when the group is already en route. The driver of the additional vehicle may have come to know of the group by inquiring the mediation server, from where he receives the corresponding communication addresses. Alternatively, he was belatedly told about the group, i.e., after the building, and provided with the corresponding communication addresses by a driver of a vehicle. Likewise, a driver of a vehicle of the group has changed his mind and wishes to leave the group at a certain point of the trip. In either case, the central server, the mediation server or the data processing units of the vehicles, respectively, receive a request from a vehicle regarding its incorporation into or release from the group. The request may be immediately granted by the receiving unit. Alternatively, such a request has first to be confirmed by the driver of the master vehicle or by the drivers of all vehicles before it can be granted.
According to a further embodiment of the invention, when during travelling a reason arises in any of the vehicles of the group for a stop, the master vehicle or all vehicles of the group receive instructions which guide them to a suitable stop, i.e., a near stop which is sufficiently spacious to admit all the vehicles. The corresponding request for a stop is generated at a vehicle by dialing a specific telephone number or by pressing a specific “stop” button. This request is transmitted to the calculating and managing unit, e.g., the central server or the data processing units of the vehicles, respectively.
It is possible that the navigation server receives information on the current traffic conditions. This information usually is provided by police, travelers, road maintenance services, meteorological service, etc. and can be gathered at a central authority, e.g., a radio station from where it is wirelessly distributed to requesting users. Preferably, this data is received by a separate traffic data reception unit of the navigation server, then this data is transmitted to the data processing unit where it is taken into account for the calculation of the route instructions. Thus, the route instructions are based not only on the static road network but also on dynamic road data.
According to a preferred embodiment of the invention, the communication unit and/or the navigation unit assigned to each vehicle comprise specific operating and/or displaying means in order to facilitate the use of the navigation service like, e.g., buttons, switches, displays, LEDs, etc. For example, when requesting at the central server to build group, it is preferable for the requesting driver to just press a button specific for this purpose, e.g., at the navigation unit. This is much more user-friendly than having to dial a certain telephone number at the communication unit. The confirmation messages received at the driver's communication unit could be visualized to the driver, e.g., by means of a blinking LED, or by a specific display on the communication unit and/or the navigation unit.